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Cosmologically Unique IDs

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Re: Cosmologically Unique IDs

#21

Post by scotty79 »

u1hcw9nx wrote: post #15
lisper wrote: post #7

This analysis is not quite fair. It takes into account locality (i.e. the speed of light) when designing UUID schemes but not when computing the odds of a collision. Collisions only matter if the colliding UUIDs actually come into causal contact with each other after being generated. So just as you have to take locality into account when designing UUID trees, you also have to take it into account when computing the o…

You must consider both time and locality. From now until protons decay and matter does not exist anymore is only 10^56 nanoseconds.

Proton decay is hypothetical.

Re: Cosmologically Unique IDs

#22

Post by Etheryte »

u1hcw9nx wrote: post #15
lisper wrote: post #7

This analysis is not quite fair. It takes into account locality (i.e. the speed of light) when designing UUID schemes but not when computing the odds of a collision. Collisions only matter if the colliding UUIDs actually come into causal contact with each other after being generated. So just as you have to take locality into account when designing UUID trees, you also have to take it into account when computing the o…

You must consider both time and locality. From now until protons decay and matter does not exist anymore is only 10^56 nanoseconds.

That's such an odd way to use units. Why would you do 10^56 * 10^-9 seconds?

Re: Cosmologically Unique IDs

#23

Post by Sharlin »

u1hcw9nx wrote: post #15
lisper wrote: post #7

This analysis is not quite fair. It takes into account locality (i.e. the speed of light) when designing UUID schemes but not when computing the odds of a collision. Collisions only matter if the colliding UUIDs actually come into causal contact with each other after being generated. So just as you have to take locality into account when designing UUID trees, you also have to take it into account when computing the o…

You must consider both time and locality. From now until protons decay and matter does not exist anymore is only 10^56 nanoseconds.

If protons decay. There isn't really any reason to believe they're not stable.

Re: Cosmologically Unique IDs

#24

Post by rini17 »

From real life we know that people prefer to have multiple anonymous IDs, or self-selected handles, either makes fully deterministic generation schemes moot.

Also, network routing requires objects that have multiple addresses.

Physics side of whole thing is funny too, afaik quantum particles require fungibility, i.e. by doxxing atoms you unavoidably change the behavior of the system.

Re: Cosmologically Unique IDs

#25

Post by antonvs »

rbanffy wrote: post #17
u1hcw9nx wrote: post #15

Earlier quoted context omitted.

You must consider both time and locality. From now until protons decay and matter does not exist anymore is only 10^56 nanoseconds.

If we think of the many worlds interpretation, how many universes will we be making every time we assign a CCUID to something?

We don't "make" universes in the MWI. The universal wavefunction evolves to include all reachable quantum states. It's deterministic, because it encompasses all allowed possibilities.

Re: Cosmologically Unique IDs

#26

Post by dylan604 »

rbanffy wrote: post #19
manofmanysmiles wrote: post #10

I'd propose using our current view of physical reality to own a subset of the UIID + version field if new physics is discovered. 10-20 bits: version/epoch 10-20 bits: cosmic region 40 bits: galaxy ID 40 bits: stellar/planetary address 64 bits: local timestamp This avoids the potentially pathological long chain of provenance, and also encodes coordinates into it. Every billion years or so it probably makes sense to re…

As for coordinates, don’t forget galaxies are clouds of stars flowing around and interacting with each other.

That's the problem with address type of systems is that they expect the object at that location to always be at that location. How do you encode the orbital speed, radius of orbit for not just the object, but also the object it is orbiting will need the same info as it is also in motion, then that object's parent galaxy's motion. Ugh, now I need a nap to calm down a bit.

Re: Cosmologically Unique IDs

#27

Post by lisper »

Etheryte wrote: post #22
u1hcw9nx wrote: post #15

Earlier quoted context omitted.

You must consider both time and locality. From now until protons decay and matter does not exist anymore is only 10^56 nanoseconds.

That's such an odd way to use units. Why would you do 10^56 * 10^-9 seconds?

This was my thought. Nanoseconds are an eternity. You want to be using Planck units for your worst-case analysis.

Re: Cosmologically Unique IDs

#28

Post by hnuser123456 »

Sharlin wrote: post #23
u1hcw9nx wrote: post #15

Earlier quoted context omitted.

You must consider both time and locality. From now until protons decay and matter does not exist anymore is only 10^56 nanoseconds.

If protons decay. There isn't really any reason to believe they're not stable.

And recent DESI data suggests that dark energy is not constant and the universe will experience a big crunch in a little more than double its current age, for a total lifespan of 33 billion years, no need to get wild with the orders of magnitude on years into the future. The infinite expansion to heat death over 10^100 years is looking less likely, 10^11 years should be plenty.

https://www.sciencedaily.com/releases/2026/02/260215225537.h...

Re: Cosmologically Unique IDs

#29

Post by rbanffy »

dylan604 wrote: post #26
rbanffy wrote: post #19

Earlier quoted context omitted.

As for coordinates, don’t forget galaxies are clouds of stars flowing around and interacting with each other.

That's the problem with address type of systems is that they expect the object at that location to always be at that location. How do you encode the orbital speed, radius of orbit for not just the object, but also the object it is orbiting will need the same info as it is also in motion, then that object's parent galaxy's motion. Ugh, now I need a nap to calm down a bit.

You could estimate when the object was labelled by the coordinates used.

But where is the Greenwich meridian for the Milky Way?

Re: Cosmologically Unique IDs

#30

Post by rbanffy »

antonvs wrote: post #25
rbanffy wrote: post #17

Earlier quoted context omitted.

If we think of the many worlds interpretation, how many universes will we be making every time we assign a CCUID to something?

We don't "make" universes in the MWI. The universal wavefunction evolves to include all reachable quantum states. It's deterministic, because it encompasses all allowed possibilities.

Humpf…

You just had to collapse my wave function here…

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